Collette Kaster, the executive director of the Professional Animal Auditor Certification Organization (PAACO), has worked with and around Butina systems since the late 1990s. She notes, “It really became meaningful for humane handling when they introduced the group loading system. You were able to move pigs as a group into the Butina. This was a continuation of what they’ve done in grow/finish, on the truck, and at the plant. The electric prods were removed at that point because the pigs moved more readily as a group. So it wasn’t gas vs. electric stunning; it’s really that the handling became a big, big difference with the group loading system.”
Increasingly, equipment manufacturers are capitalizing on the group handling benefits of using a CAS system. SFK LEBLANC started working with Danish hog slaughter plants in 1931, and has been involved in developing advanced systems for pork slaughter and processing ever since. Today, the company offers a state-of-the-art integrated controlled atomosphere stunning system which incorporates the handling benefits of group
pig movement.
With North American offices in Kansas City, Missouri, and Quebec City, Quebec, SFK LEBLANC’s CO2 Stunning System delivers optimum animal welfare, hygienic design and safety for stunning operators. The automated pig handling system leads groups of animals into gondolas where SFK LEBLANC’s patented CO2 system renders the animals insensible before being tipped out of the stunner and onto a conveyor for shackling. In addition to the welfare benefits of group handling, the company’s integrated system provides a quieter environment for the pigs.
“Noise levels in the barns and the lairage/stunning areas were reduced by 20 percent with the CO2 stunning system, providing a stress-free environment,” the company reports.
Innovative Approach to Induction
The Humane Aire Controlled Atmosphere Stunning system built by Midwest Machine Technologies of Zeeland, Michigan, has an innovative approach to CO2 stunning that overcomes the issue of adverse reactions by poultry. Developed by engineer Roger Draft, the Humane Aire system utilizes low stress handling technology from the farm all the way through to slaughter.
Terry Geertman of Midwest Machine describes an attribute that has made the Humane Aire system uniquely successful. “One important point differentiates our system from others. Other systems use a gradual fill to achieve induction. Gradual fill is when you take the CO2 from zero and you bring the level up until the bird goes unconscious. It is during this process that the birds become agitated. The most effective induction was to have a chamber precharged with 30 percent CO2, but the existing CO2 sensors prevented that from happening. We did the research and developed a proprietary sensor that holds the level at 30 percent and allows for a quicker induction.”
After the induction phase, the birds are conveyed through an air lock into the second stage at a higher C02 level to achieve the irreversible stun. “We’re a two-stage process – induction and irreversible stun,” Geertman says.
